Tiltable steering column lock mechanism

Abstract

The tiltable component in a tilt type vehicle steering column can be locked in selected positions of adjustment by an external locking mechanism that includes an elongated rod having pivot connections with the stationary and movable components of the column. A rotatable locking sleeve encircles the rod to form a rigid connection between the rod and one of the pivot connections. Meshed teeth on the rod and sleeve prevent the rod from moving in the longitudinal direction. By rotating the sleeve on the rod it is possible to shift the teeth out of mesh, such that the rod can move longitudinally to set the movable component of the steering column in a new selected position of adjustment.

What is claimed:  
     
       1. An articulated tiltable steering column comprising an upper steering wheel column member, a lower stationary steering column member, a pivot connection between said upper and lower column members, whereby a steering wheel can be tiltably adjusted around the pivot connection to selected positions of adjustment; and 
       a locking mechanism for retaining said column members in selected positions of adjustment, said locking mechanism comprising an externally threaded rod trained between the column members, and an internally threaded sleeve encircling said rod;  
       said rod having a longitudinal axis; said rod having a first pivot means connecting the rod to one of the column members, and a second pivot means connecting the rod to the other column member;  
       said second pivot means comprising a pivot shaft carried by said other column member and an axial slot in said rod slidable on said pivot shaft;  
       said sleeve having a circumferential slot embracing said pivot shaft; said rod comprising a first set of circumferentially discontinuous external teeth; said sleeve comprising a second set of circumferentially discontinuous internal teeth; said internal teeth being in mesh with said external teeth when said sleeve is rotated in one direction; said internal teeth being out of mesh with said external teeth when said sleeve is rotated in the opposite direction.  
     
     
       2. The steering column of claim  1 , wherein said rod has two flat parallel side surfaces and two toothed surfaces spanning said side surfaces; said sleeve having two diametrically opposed toothed surfaces separated by two non-toothed surfaces; 
       said sleeve being rotatable on said rod so that in a first rotated position of said sleeve the toothed surfaces on the sleeve and rod are in mesh, and in a second rotated position of said sleeve the toothed surfaces on the sleeve and rod are out of mesh.  
     
     
       3. The steering column of claim  2 , wherein the non-toothed surfaces on said sleeve are arcuate surfaces having the same diameter as the toothed surfaces on rod, whereby the sleeve is maintained in a centered position on the rod when the sleeve is in the second rotated position. 
     
     
       4. The steering column of claim  1 , wherein said locking mechanism further comprises spring means for rotating said sleeve in said one direction, and a manual cable means for rotating said sleeve in said opposite direction. 
     
     
       5. The steering column of claim  4 , wherein said spring means comprises a torsion spring encircling said sleeve. 
     
     
       6. The steering column of claim  4 , wherein said manual cable means partially encircles said sleeve.